Random noise captured by digital cameras may degrade the quality and authenticity of resulting digital images. For example, when a digital camera capture images in low-light conditions, an image sensor on the digital camera may receive insufficient light, which may result in an under-exposed image. The under-exposed image may appear faded and blurry due to noises in image pixels. Furthermore, inexpensive camera sensors found in some mobile electronic devices such as smartphones and tablets may exacerbate the problem by introducing additional noise. Thus, denoising filters configured to reduce or remove noises from images may help improve image quality.